Fluidic safing-arming system

ABSTRACT

A safing and arming system requiring no moving parts or electronic components. When both ram air and exhaust gas are applied to the system, a fluid oscillator and a fluidic binary counter are rendered operative. After the binary counter counts a predetermined number of oscillations, a pressure signal is transmitted to an AND gate which, upon coincidence of that signal and exhaust gas, transmits a signal to a pressure-activated switch arming the missile.

United States Patent Campagnuolo et al. 1 Feb. 4, 1975 {54] FLUIDICSAFlNG-ARMING SYSTEM 3,229,638 1/1966 Woolston et a] 102/81 X 7 '7Inventors: Carl J p g Chevy Chase; 3,..37,7l. 3/1966 Horton 181/5Charles F. Peer, Silver Spring, both of Md. Primary Examiner-Samuel W.Engle i731 Assignee The United States of America as g Firm-NathanEdelbflg; Robert represented by the Secretary of the lbson Saul aumArmy, Washington, DC

[22] Filed: Oct. 24, 1966 ACT [2]] Appl. No.: 589,128 A safing andarming system requiring no moving parts or electronic components. Whenboth ram air and ex- [52] U S Cl 102/81 haust gas are applied to thesystem, a fluid oscillator {51] 5/00 and a fluidic binary counter arerendered operative. [58] Fie'ld 2 82 764 After the binary counter countsa predetermined num ber of oscillations, a pressure signal istransmitted to an AND gate which, upon coincidence of that signal [56]References Cited and exhaust gas, transmits a signal to apressureactivated switch arming the missile, UNITED STATES PATENTS1,297,273 3/1919 Straub et al, l02/8l ll Claims, 1 Drawing Figure EEG,UL A Torr 7 /00 A NK 4 7 g 1 #2 4/3 iii /43 REG uz. A TO}? 90 AND NZ 0 5w/ TCH 4; .2 i

6/ 1/22 i4 4 B/ASED AMPL lF/Efi 5 4 8 OJC/LL ATO/i? 9 p 2 6 B/N/lf? vcom/7'0? PATENTEU FEB 41975 NuW/ I MGR 3b wmqw INVENTORS CARL JCAMPAGNUOLO CHAR-LE5 F PEER ATTORNEYS 1 FLUIDIC SAFlNG-ARMING SYSTEMThis invention relates to an ordnance arming device and in particular toa pure fluid arming system.

The typical explosive weapon can be placed in either an armed or unarmedcondition. In the armed condition the weapon will be detonated uponreceipt of a firing impulse. Most firing devices are set to send afiring impulse upon the weapon being near or at a designated target.Typical firing impulse generating means are proximity devices, timerdevices and impact devices. In the unarmed condition the weapon will notbe detonated upon receipt of a firing impulse.

Great care must be exercised in using explosive weapons to maintain theweapon in an unarmed condition during launching and for a sufficienttime after launching to protect the launching crew from detonation bythe accidental receipt of a firing impulse. It is equally important thatthe weapon be armed as it ap proaches target so as to detonate in thevicinity of the target upon receipt of the target oriented firingimpulse.

Modern weapon technology has undergone great advances in the last fewyears. lt is no longer a rarity for a modern weapon carrying missile tooperate from Mach one to Mach four velocities, undergo acceleratins upto g and altitudes up to l00,000 feet. The high speeds and altitudes ofmodern weapon carrying missiles have subjected the missile armingcontrols to shock, vibration. pressure and temperature extremes notpreviously known in older and slower missiles. The greater physicaldemands on arming systems have made electronic arming systemsundesirable because of their inability to function effectively duringsevere missile vibrations, as would be found at Mach four velocities andaccelerations of 20 g. Mechanical arming systerns are adversely affectedby wear and friction and are similarly undesirable because of the hightolerances required by component elements, and hence high cost.

Pure fluid systems have only recently been invented and rely onn theinterchange of momentum of two fluids to obtain a controlled output.Pure fluid devices are not adversely affected by vibrations and becauseno moving parts are required are easy to make at a nominal cost. Thepresent invention utilizes pure fluid devices to arm a weapon carryingmissile at a predeter mined time, and hence distance, from the launchingmeans.

Briefly, the present invention utilizes the ram air of the weaponcarrying missile and the exhaust gases of the missile to provide twosignals for a pure fluid arming system. Upon receipt of both signals apure fluid circuit, after a predetermined delay, will send a fluidsignal to an arming mechanism, carried by the missile, arming themissile for detonation upon receipt ofa firing impulse.

It is therefore an object of the present invention to provide for thearming of a weapon-carrying missile at a safe distance away from thelaunching crew and before the missile reaches the target.

It is a further object of the present invention to provide means to arma weapon carrying missile that is insensitive to missile speed, missileshock, missile vibration, and environmental temperature and pressureextremes.

Still another object of the present invention is to provide means to arma weapon carrying missile utilizing the ram air and exhaust gases of themissile and no external power source.

A further object of the present invention is to arm a weapon carryingmissile upon receipt of plural signals.

Another object of the present invention is to provide means toaccurately vary the delay time in a weapon carrying missile beforearming the weapon.

Other objects, aspects and advantages of the present invention willclearly appear from the following description and from the accompanyingdrawing in which:

The drawing is a schematic illustration ofa pure fluid arming device inaccordance with the present invention.

In the drawing an arming circuit is shown as being positioned outside aweapon carrying missile 10 that it is to arm. It is to be understoodthat normally the arming circuit is positioned inside the missile but isshown in FIG. 1 without missile H) for illustrative purposes only. A ramconduit 13 leads to the nose ll, or any appropriate place. of missile l0and is adapted to receive the ram air of the missile. Ram conduit 13leads to left control 60 of a biased fluid amplifier 22. Biased fluidamplifier 22 has output conduits 24 and 25. The amplifier is biased todischarge from conduit 24 in absence of a fluid signal applied tocontrol conduit 60. The bias could be accomplished by any of theconventional ways, such as setting the splitter to be closer to conduit24, or as shown in U.S. Application Ser. No. 588,677 filed Oct. l9, I966by Elmer Swartz for a Self-Biasing Fluid Amplifier," now U.S. Pat. No.3,442,279. Line 23 is a schematic representation that the amplifier isbiased to conduit 24 in absence of a fluid signal to control conduit 60.

Conduit 24 leads to ambient while conduit 25 leads to a binary counter26 and acts as the pressure supply therefor. Binary counter 26 couldconsist of a number of stages and is any of the well known fluid binarycounters that upon the simultaneous receipt of two pressure signalswill, after a predetermined delay, emit a fluid signal. One commercialcounter stage that could be used is made by the Coming Fluidic Devicesdepart ment of Coming Glass and is identified by catalogue numberFD-27l2-Z-32l l. Exhaust gases 14 by conduit 15 communicate with a checkvalve 16 which is positioned to direct flow from conduit 15 to conduit18 but stop flow in the reverse direction. Conduit 18 leads to astagnation tank 17. Stagnation tank 17 is an enclosed volume whichserves to increase the static pres sure of the fluid therein at theexpense of the fluid velocity in a manner well known in the art. Aconduit 40 communicates stagnation tank 17 with a pressure regulator 41.Pressure regulator 41 could be any of the conventional pressureregulators or an orifice plate. An orifice plate is merely a plate witha small orifice in the middle of it. Flow is directed against the plateand the size of the orifice determines the amount of fluid to be passedthrough the plate. The fluid not passed through the orifice is vented toambient. A conduit 19, by a regulator 20 and a conduit 21, suppliesexhaust gases to the power nozzle (not shown) of biased amplifier 22.Regulator 20 could be an orifice plate as regulator 41 and serves toreduce the pressure to biased amplifier 22. A conduit 42 communicatespressure regulator 41 with AND unit 43. The AND unit could be any one ofthe well known units now commercially available. AND unit 43 has outputconduits 44, 45 and 90. A conduit 52, along with conduit 42 supplies thefluid signals to the unit. Upon receipt of fluid from only conduit 52AND unit 43 will discharge fluid to the ambient by conduit 90. if onlyconduit 42 sends fluid to AND unit 43 the fluid will be discharged fromconduit 44 while if fluid is supplied to the AND unit by conduits 42 and52 the AND unit will discharge fluid from conduit 45. Conduit 45 leadsto a pressure-actuated switch 46 which, when activated, serves tocomplete an electrical circuit which will arm the missile. Obviously anytype of pressure triggered arming means could be used and the use of anelectrical circuit is for illustrative purposes only. Conduit 44 leadsto a fluid oscillator 48 which has a left output conduit 49 and a rightoutput conduit 50, the latter which is communicated to atmosphere.Conduit 49 serves to communicate the oscillator to conduit 51 whichserves to supply fluid to binary counter 26 along with conduit 25.Because of the fluctuations in the pressure and temperature of theexhaust gases it is desirable that the frequency of oscillator 48 beinsensitive to both pressuure and temperature changes. It is thereforepreferable that the oscillator be built in accordance with U5.Application Ser. No. 595,538 filed Nov. 18. 1966 by Carl J. Campagnudoet al.. for a "Pressure and Temperature insensitive Systern," now US.Pat. No. 3,504,691.

When missile is in its launching means a plug could be put in ramconduit l3 and connected to the launching pad by a string. This wouldprevent a burst of wind from entering ram conduit 13 and supplying afalse signal to the arming circuit. Before launching, the rockets willbe firing and exhaust gases will be gathered and directed by conduit 15through check valve [6 by conduit 18 to tank 17. Conduit 19 will directfluid, by regulator 20 and conduit 21, to biased amplifier 22. The fluidwill initially be vented out conduit 24 because of the built in bias. Nofluid will be received by ram conduit 13 when the missile is in itslaunching means to overcome the bias means. Conduit 40 will directexhaust gases from tank 17 to regulator 41 which will reduce thepressure of the exhaust gases for AND unit 43. If an orifice plate isused for regulator 41 the size of the orifice can be varied to controlthe pressure of fluid directed to AND unit 43. The AND unit will receiveone signal from conduit 42, when the mimssile is in the launching means,and will therefore direct fluid to conduit 44. Since no ram fluid isreceived by control conduit 60, conduit will not direct fluid to binarycounter 26. The binary counter requires two signals to direct fluid toconduit 52, and since only conduit 51, as will be seen, will directfluid to the counter, no fluid signal will be supplied to conduit 52.Fluid directed to conduit 44 will enter fluid oscillator 48 Where itwill alternately be discharged from conduit 49 and conduit 50, thelatter conduit communicated to atmosphere. Conduit 49 will direct fluidto binary counter 26 by conduit 51. The binary counter will not directfluid to conduit 52 since a second fluid signal will not be directed tothe binary counter by conduit 25. Arming switch 46 will not be activatedsince AND unit 43 will not direct pressure to conduit 45, as the ANDunit will direct fluid to conduit 44 upon receipt of a signal fromconduit 42 alone. When the missile leaves the launching means the plugin the end of ram conduit 13 will be 6 removed by the string attachrngIt to thelaunchmg means allowing ram air to enter ram conduit 13 andcommunicate to control conduit of biased amplifier 22. This will switchthe output of biased amplifier 22 to conduit 25 which will direct fluidto binary counter 26. Conduit 51 will continue to direct fluid to binarycounter 26 during actual flight combining with conduit 25 to give thenecessary two signals to the binary counter. The binary counter, afteran appropriate delay will, by conduit 52, direct a signal to AND unit 43which will be also receiving a signal from conduit 42 giving the unitthe necessary plural signals to direct fluid to conduit 45 and topressure arming switch 46. The switch will be activated completing anelectrical circuit which will arm the missile.

The delay time (r) for the binary counter to send an arming signal toAND unit 43 is determined by the following formula:

where n is the number of counter stages andfis the oscillator frequency.Since the oscillator frequency is insensitive to temperature andpressure fluctuations it can be seen that by using a predeterminednumber of counter stages and a particular oscillator frequency a desiredtime delay can be obtained.

It can readily be seen that we have provided a simple means to arm aweapon carrying missile away from the launching means after a designatedtime delay.

We claim as our invention 1. In a weapon carrying missile powered byexhaust gasses an arming system. comprising:

a. means for receiving a portion of said exhaust gas;

b. means for receiving ram air;

c. a fluid amplifier supplied with a source of power fluid having acontrol conduit connected to said means for receiving ram air, saidamplifier having first and second output conduits and including means todirect said power fluid out said first conduit in the absence of ram airand out said second output conduit upon the application of ram air tothe system;

d. an AND gate having two input conduits and at least two outputconduits; one input of said AND gate being connected to said means forreceiving exhaust gas;

e. a fluidic oscillator having an input conduit connected to one of saidoutput conduits of said AND gate so that said oscillator is renderedoperative when exhaust gas only is applied to said AND gate;

. a fluidic binary counter connected to said second output conduit ofsaid fluid amplifier such that said counter is rendered operative uponthe application of ram air to the system. and connected to an output ofsaid fluid oscillator. the oscillations of which are counted by saidcounter;

g. means connecting said binary counter to the other of said inputs ofsaid AND gate for directing a sig nal to said AND gate after saidcounter has counted a predetermined number of oscillations; and

h. a pressure-activated switch for arming said missile connected to theother of said outputs of said AND gate so that it will receive apressure signal upon the coincidence of input signals to said AND gate.

2. A device according to claim 1 wherein said fluid oscillator has afrequency and includes means to render said frequency insensitive tochanges in temperature and pressure of said exhaust gases.

3. A device according to claim 1 wherein said power fluid for saidamplifier is said exhaust gases.

4. A device according to claim 3 wherein:

a. said exhaust gases are communicated to a stagnation tank. and

b. a conduit communicates said stagnation tank and said amplifier.

5. A device according to claim 4 wherein a conduit communicates saidstagnation tank with said AND unit.

6. A device according to claim 5 wherein a pressure regulator is placedin said conduit which communicates said stagnation tank and said ANDunit.

7. A device according to claim 4 wherein a pressure regulator is placedin said conduit communicating said stagnation tank and said amplifier.

8. In a weapon carrying missile, an arming system, comprising:

a. a pressure activated means for arming said missile;

b. a means associated with said missile for receiving a plurality offluid signals; and

c. a fluid circuit means for actuating said pressureactivated means inresponse to and a predetermincd time after the coincidental receipt ofsaid plurlity of fluid signals, said fluid circuit means including adelay means in which all the operating elements are stationary exceptfor the working fluid for determining the length of the time periodbetween the receipt of said plurality of fluid signals and the actuationofsaid pressure-activated means.

9. The arming system of claim 8 in which said delay means is a fluidictiming circuit.

10. The arming system of claim 9 in which said fluidic timing circuitcomprises a fluidic binary counter. means for initiating the operationof said counter upon the application of one of said plurality of fluidsignals to said arming system. and a fluidic oscillator providing asignal to be counted by said binary counter upon the application ofanother of said plurality of signals.

11. The arming system of claim 8 utilized in a missile powered byexhaust gasses in which said plurality of fluid signals comprises aportion of said exhaust gas and ram air.

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1. In a weapon carrying missile powered by exhaust gasses an armingsystem, comprising: a. means for receiving a portion of said exhaustgas; b. means for receiving ram air; c. a fluid amplifier supplied witha source of power fluid having a control conduit connected to said meansfor receiving ram air, said amplifier having first and second outputconduits and including means to direct said power fluid out said firstconduit in the absence of ram air and out said second output conduitupon the application of ram air to the system; d. an AND gate having twoinput conduits and at least two output conduits; one input of said ANDgate being connected to said means for receiving exhaust gas; e. afluidic oscillator having an input conduit connected to one of saidoutput conduits of said AND gate so that said oscillator is renderedoperative when exhaust gas only is applied to said AND gate; f. afluidic binary counter connected to said second output conduit of saidfluid amplifier such that said counter is rendered operative upon theapplication of ram air to the system, and connected to an output of saidfluid oscillator, the oscillations of which are counted by said counter;g. means connecting said binary counter to the other of said inputs ofsaid AND gate for directing a signal to said AND gate after said counterhas counted a predetermined number of oscillations; and h. apressure-activated switch for arming said missile connected to the otherof said outputs of said AND gate so that it will receive a pressuresignal upon the coincidence of input signals to said AND gate.
 2. Adevice according to claim 1 wherein said fluid oscillator has afrequency and includes means to render said frequency insensitive tochanges in temperature and pressure of said exhaust gases.
 3. A deviceaccording to claim 1 wherein said power fluid for said amplifier is saidexhaust gases.
 4. A device according to claim 3 wherein: a. said exhaustgases are communicated to a stagnation tank, and b. a conduitcommunicates said stagnation tank and said amplifier.
 5. A deviceaccording to claim 4 wherein a conduit communicates said stagnation tankwith said AND unit.
 6. A device according to claim 5 wherein a pressureregulator is placed in said conduit which communicates said stagnationtank and said AND unit.
 7. A device according to claim 4 wherein apressure regulator is placed in said conduit communicating saidstagnation tank and said amplifier.
 8. In a weapon carrying missile, anarming system, comprising: a. a pressure activated means for arming saidmissile; b. a means associated with said missile for receiving aplurality of fluid signals; and c. a fluid circuit means for actuatingsaid pressure-activated means in response to and a predetermined timeafter the coincidental receipt of said plurlity of fluid signals, saidfluid circuit means including a delay means in which all the operatingelements are stationary except for the worKing fluid for determining thelength of the time period between the receipt of said plurality of fluidsignals and the actuation of said pressure-activated means.
 9. Thearming system of claim 8 in which said delay means is a fluidic timingcircuit.
 10. The arming system of claim 9 in which said fluidic timingcircuit comprises a fluidic binary counter, means for initiating theoperation of said counter upon the application of one of said pluralityof fluid signals to said arming system, and a fluidic oscillatorproviding a signal to be counted by said binary counter upon theapplication of another of said plurality of signals.
 11. The armingsystem of claim 8 utilized in a missile powered by exhaust gasses inwhich said plurality of fluid signals comprises a portion of saidexhaust gas and ram air.